Process for drying moisture-containing materials



Fkb.24.1925. -L52Z193 J.JUDELSON PROCESS FOR DRYING MbISTuRE CONTAiNINGMATERIALS Filed Jan. 7, 1921 2 Sheets-Sheet 1 'T'Tq. 1.

INVENTOR dbl/ow QQzozCLJzMv ATTORNEYS Feb. 24. 1925. 1,527,193

J. JUDELSON PROCESS FOR DRYING MOISTURE CONTAINING'M'ATERIALS F iledJan. '7, 1921 2 Sheets-sheet 2 INVENTOR JuuuJ Juons 01v ATTORNEYSPatented Feb. 24, 1925.

UNITED STATES JULIUS JUDELSON, OF NEW YORK, N. Y., ASSIGNO'R T JUDMSONEVAJP'O-DRYER COR- PORATION. CORPORATION OF YORK.

PROCESS FOR DRYING MOISTURE-CONTAINING- MATERIALS.

Application filed January 7, 1921. SerialNo. 435,709.

To all whom it may concern: Be it known that JULIUS JUDELsoN, a citizenof the United States and resident of the city of New York, in the countyof Bronx and State of New York, has invented certain new and usefulImprovements in Processes for Drying Moisture-Containing Materials, ofwhich the following is a specification.

This invention relates to a process for drying moisture containingmaterials.

Oneobject thereof is to provide a process of this character which shallbe etiicient in operation to a high degree.

Another object is to provide a process of the character described whichshall be easy and simple to carry out and require comparative'ly simpleand inexpensive apparatus. Other objects of this invention will be inpart obvious and in part hereinafter pointed out.

scribed are shown, described and claimed in my co-pending applicationSerial No. 435,708 filed Jan. 7, 1921, for Dryers and accordingly arenot claimed herein.

The process will be best understood by reference to the drawing in whichare shown a preferred form of apparatus for carrying out the process,and in which Fig. 1 is a longitudinal cross-sectional view of theapparatus; and

Fig. 2 is an end view of the dryer with an end wall of the teasingremoved and partsbroken away to expose the means for exhausting and forrecirculating the drying medium.

The apparatus herein described and shown forms the subject matter of myco-pending application Serial No; 435,708 filed Jan. 7, 1921 forevaporators, and is seen to-comprise the casing preferably ofdoublewalled construction so as to include heat insulating air spaces 11for preventing loss of heat from the interior of the dryer. The

casing 10 is provided at one end with a passage 12 into which issupplied air or any other suitable vehicle through a conduit 13 which issuitably connected? to a blower 14 of suitable type and which is secured"preferably to the top of the casing as shown by means such as bolts 15.Located preferably in the passage 12 is a heating device such as thesteam pipes 16 (shown diagrammatically) for preheating the airsuppliedto the passage to any desired temperature. On the interior ofthe casing and occupying substantially a greater portion of the volumethereof is the drying chamber 17, at the end of which adjacent the,supply passage 12 is the'passage 18 communicating at the bottom withthe supply passage 12 at terminus 19. Located in this passage 18 isanother heating device such as the steampipes 20 shown diagrammatically.Disposed at the other end of the chamber 17 is a passage 21communicating at the top with a series of return flues 22 extendingabove the drying chamber 17 and down into the supply end of theevaporator and terminating at and communicating with the chamber 18 asshown at 23.

Located in the return passage 21 1s a fan 24 suitably mounted on a shaft25 adapted to be driven by a motor (not shown). The fan is'preferablyconstructed Certain features herein shown and de-.

so that the planes of the vanes 26 thereof do not pass through the axisof the fan shaft but are turned at various angles thereto as shown in myco-pending application above referred to. Opening from the bottom of thepassage 21 is an exhaust flue 27 provided with a damper device 28.Beneath the fan 24 is provided a triangular venting device or louvers 29comprising metal strips 30, angularly disposed adjacent each other asshown in Fig. 2, and forming the sides of the triangle and providingbetween their ends openings 31 through which the passage 21 communicatesthrough the space 32 at the bottom of the passage with the opening 33of'the flue.

The drying chamber 17 is open at each end and is provided at,each endwith spaced supporting pieces 34, 35. To the inner support 35 aresecured angle irons 36 which serve to support trays "37 on which areplaced the layers of material to be dried.

Secured to the outer supports 34 are bent deflecting pieces 38 havinghorizontal /portions 39 substantially parallel to horizontal supportingflanges 40 on the angle irons 36, and forming between the horizontalportions 39 of the pieces 38 and said flanges 40, passageways 41 and 41'oppositely disposed in each end of the drying chamber, said passageways41 and 41' serving to direct the drying'medium across the top and bottomof the tray 37.

In carryingc'out my process, the heat vehicle such as air or the likemedium is drawn in from the outside by means of the blower 14 and passedover the heating device such as the steam coil 16 so as to heat it toany desired temperature. As will be clear from the drawing, the dryingmedium is supplied throu h the conduit 13 and after being heate 'entersthe chamber 17 through the delivery terminus 19 at the bottom thereof.This heated medium rises into the passage 18 and expands and difiusesinto the chamber 17 through thepassageways 41 as indicated by the arrowsin full lines. The heat medium is drawn through the chamber in thedirection of the horizontal arrows in Fig. 1 contacting with the layersof material on the trays both above and underneath the same, andabstracts some of the moisture from the wet materials as will be readilyunderstood. The drying medium with the moistufe thus evaporated thereinpasses through the openiifgs 41' into the passage 21, where it is actedupon by the. fan '24, which is revolved in the direction shown by thearrow in Fig. 2. In the passage 21, the operation of the fan 24 aids indrawing the drying medium at a comparatively rapid rate through thecompartment 17 and serves to force a portion of the moisture laden orused drying medium drawn into the passage 21 downward under the actionor suction of the draft throu h the openings 31 in the vent 29 to the exaust flue 27, the amount of drying) medium thus exhausted beingregulated y the dam er 28. Anotherportion of the moist m 'um is forcedupwardly through the return flues 22. It has been found in actualoperation of dryers embodying this invention that the moisture contentsin the medium being exhausted beneath the fan 24; is higher than that inthe portion returned for circulating above the fan, the co-action of thevarious elements of the apparatus and their arrangement being effectiveto remove a large (portion of the moisture with the exhausting medium.The

. fan 26 is revolved at a speed to impart to the returning drying mediumsuflicient pressure to recirculate the said medium against thepropulsion pressure of the fresh air supply by the blower. The returnmedium is propelled through the flues 22 and past the reheating steamcoils-20 whereby suflicient heat is supplied to the return drying mediumto-compensate for the reduction in temperature consequent to its firstpassage throu h the drying chamber,

and contact with t e moist materials. At

the co-terminus 19, the return drying medium which has now been reheatedmixes with the fresh suppl'. and is again uniform- 1y and simultaneous ycirculated under and above all of the trays 37. It will be noted thatthe fresh supply of air and the return drying medium in part again passbythe reheater 20 in rising into the passage 18.

This insures a heated drying medium of definite temperature to besupplied ihto the drying chamber 17 and has the further advantage thatthe trays further removedjrom 'the (bottom of the drying chamber andfrom the supply or delivery portion 19 will be acted upon by a'dryingmedium of substantially the same temperature as those near the bottom ofthe chamber and closer to the terminus 19; for it will of course beunderstood that the trays in'the lower porloss is compensated for by thefact that the medium in rising up into the chamber 18 at the same timeasses over the reheater. 20. In this way, this reheater aids inmaintainin a substantially constant temperature throughout the whole (1ingchamber.

It will thus be seen t at there is provided a process in. which theseveral objects of this invention are achieved and which is well adaptedto effectively and efiiciently meet the needs of practical use.

Having thus described my invention, I claim as new and desire to secureby Letters Patent p 1: The process of evaporating moisture frommaterials to be dried consisting in heating a drying medium to apredetermined temperature, circulating the same into contact with thematerial to evaporate some of the moisture therefrom, withdrawing themoisture-laden drying medium and simultaneously exhausting a portionthereof, and recirculating another portion of the medium to contact withthe material, and

reheating said latter portion to compensate for the temperature lossthereof by reason of the first contact with the material.

2. The process -of eva orating moisture from materials to be driedbonsistmg in pass ing a drying medium into a chamber con, taining thematerial and allowing said medium to contact with the latter toevaporate some of the moisture therefrom, withdrawing the moisturecontaining medium from the chamber, exhausting a moisture laden portionof the medium and simultaneously returning another portion of saidmedium to the chamber into re-contact with the material and reheatingthe latter portion during the return passage thereof.

3. The process of evaporating moisture from materials to be driedconsisting in placing the materials in spaced vertical layers in adrying chamber, applying a dryi- 130 iqg medium to said chamber, passingas.

margins medium through or in contact with a heating device to heat themedium to a predetermined temperature before it enters the chamber,allowing said medium to contact with the materials in the chamber toevaporate some of the moisture therefrom, drawing the moisturecontaining vehicle through the chamber, exhausting a moisture ladenportion of the medium, then propelling another portion of said vehicleback past the heating device and permittin the returned medium tocontinuously mix with a fresh medium supply and then recirculating itthrough the chamber together with the fresh supply.

- of the material to evaporate some of the moisture therefrom, drawingthe moisture containing medium through the chamber,

exhausting the moisture laden portion of the heat vehicle, reheating theremaining portion of said drying medium and returning the latter throughthe chamber. I

5. The process of evaporating moisture from materials to be driedconsisting in placing the materials in a drying chamber, drawing throughsaid chamber a drying medium preheated to a desired temperature,simultaneously exhausting a moisture laden portion of the medium, andreturning another portion to the intake end of the chamber, reheatingthe latter portion during the return passage thereof, and again drawingthe medium through the chamber.

6. A process of drying materials consisting in placing the material inspaced vertical layers in a compartment, passing a preconditioned dryingmedium across the compartment in one direction between the said layersto contact with the materials to evaporate moisture therefrom,exhausting a portion of the moisture laden medium, and simultaneouslyreturning another portion for recirculation and preconditioning thelatter portion during the return passage thereof.

Signed at New York city, in the county of New York and State of NewYork, this 30th day of December, A. D. 1920.

JULIUS JUDELSON.

